Re: Execute query with EXCEPT, INTERSECT as anti-join, join?

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От Tom Lane
Тема Re: Execute query with EXCEPT, INTERSECT as anti-join, join?
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Msg-id 15498.1384176883@sss.pgh.pa.us
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Ответ на Execute query with EXCEPT, INTERSECT as anti-join, join?  ("Colin 't Hart" <colinthart@gmail.com>)
Ответы Re: Execute query with EXCEPT, INTERSECT as anti-join, join?  ("Colin 't Hart" <colin@sharpheart.org>)
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"Colin 't Hart" <colinthart@gmail.com> writes:
> I can't get Postgresql to execute a query with EXCEPT (or INTERSECT)
> as an anti-join (or join).

> Is this even possible?

No, and it probably won't ever be, since the semantics aren't the same.
EXCEPT/INTERSECT imply duplicate elimination.
        regards, tom lane



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